Fast gun?

[Scott Tschirhart]

I have a question. Is this even possible?

I set up my chronograph to test some loads in a 7.5 inch Super Redhawk.

Skeeter loads are consistently clocking 950 fps in my Bowen 4 5/8 inch Blackhawk. So I expected a bit of increase from a 7.5 inch barrel. This load clocked:

1015
999
1005
1022
1009

This is just about what I expected.

[Scott Tschirhart]

Then I got out some white box Winchester 240 gr soft point.

1815
1800
1811
1809
1830

These are carbine velocities!!!!

[Scott Tschirhart]

This shouldn’t happen. So I changed batteries and backed off another 10 feet or so from the chronograph.

1760
1762
1754
1726
1757

This is still looking strangely high.

[High Desert Hunter]

Wow! Those are smokin'! I have had issues with Win White Box in 45 ACP, they were way over pressure. Those are close to 454 Casull numbers.

[Old Savage]

One chronograph I had jumped about 400 fps on low battery.

[Scott Tschirhart]

That’s why I changed the battery.

This same box of ammo clocked from a 20 inch Marlin on October 8, 2023:

1793
1785
1769
1767
1777

I don’t believe that my readings today can possibly be accurate.

[earlmck]

I'm guessing those are true readings Scott. As I played around in QuickLoad, it says a compressed load of Lil' Gun under a 240 grain XTP would clock those velocities but be 46k psi vs SAAMI 36k. Those would be hot loads according to SAAMI but would probably not give any noticeable pressure indications in the way of sticky extraction. I told it we had a 9" bbl, adding 1.5" for the cylinder, and used 27.5 gr. of the Lil' Gun and it calculated we'd get 1790 fps.

[GunnyMack]

Sounds like false numbers Scott. Sky screens? Bright sun or overcast?

I got 1820±/‐ with 210gr 41 mags with lilgun out of 20" and questioned the load, another test on a different day showed the same.

I'd say test them on a different day.

[LeverGunner]

Wow! You should test a known load and gun and see if it's correct there. I've heard of there being a 200-300 fps difference between similar barrel lengths out of different guns, but that's pretty excessive.

[samsi]

I recall that the WWB 240 load has been discussed here as pretty speedy in carbines, but those numbers are suspicious. Even with tight throats and minimal cylinder gap I wouldn't expect that kind of increase. On the plus side, that beefy Redhawk cylinder isn't going to let go.

Are the velocity numbers on the box for a 4" barrel? Even at that I'd expect a max increase of around 200 fps going from 4 to 7 1/2.

[Scott Tschirhart]

Sounds like false numbers Scott. Sky screens? Bright sun or overcast?

I got 1820±/‐ with 210gr 41 mags with lilgun out of 20" and questioned the load, another test on a different day showed the same.

I'd say test them on a different day.

Sky screens and bright sunshine.

The odd thing is that the Skeeter loads are just where I would expect them to be.

[GunnyMack]

The unknown is what powder is in the factory ammo? It could be some blend we can't get and they are just shown as Xfps so if anybody complained then Winchester could say SEE - this is what they actually are doing.
OR
maybe just maybe your Redhawk is just the perfect storm of barrel dia, throat, forcing cone , barrel cylinder gap and everything is just right giving you that exactly right combo.
But on the other hand, I might be full of horse feathers!
Know anyone else who has a 7.5 Redhawk to try them in ?

[Walt]

Do you know someone else who owns a chronograph who might let you check your velocities on theirs to see if they match?

[Scott Tschirhart]

I don’t shoot with anyone else. I just use my range on the ranch.

I’ll change the battery again and try it out on a different day and compare with something I know is consistent

I think I’ll load up some warm 2400 loads and see.

[Griff]

I'd load up a cylinder full of alternating between the factory stuff and your handloads. If the velocity of that factory ammo is to be believed, you should have a very appreciable difference in felt recoil. Not as scientific, but...

[Walt]

Looking back at my notes, I loaded just 20.5 gr of 2400 behind a 429244 GC bullet in a 4 5/8" Super Blackhawk and got 1375 fps. Not as fast as your loads but not as much of a stretch as I initially thought. It felt like a pretty hot load to me despite being somewhat less powder than Lyman's published max.

[Scott Tschirhart]

maybe just maybe your Redhawk is just the perfect storm of barrel dia, throat, forcing cone , barrel cylinder gap and everything is just right giving you that exactly right combo.

I measured the throats and they are a slip fit for a .430 diameter bullet. Actually bigger than I thought but they seem to be uniform.

[Scott Tschirhart]

The gun is fast, but not that fast.

New battery and overcast sky.

New box of Winchester White Box

1485
1479
1486
1501
1466

Empty cases fall freely from the chambers.

[GunnyMack]

Did you have any of the other box to try as well?
Not sure what powder Winchester uses, of course it's different than we can buy but still a fast load for sure!

[Scott Tschirhart]

22 gr 2400 is wonderfully accurate. But it’s too hot with sticky extraction.

1688
1663
1657
1648
1654

[Scott Tschirhart]

Did you have any of the other box to try as well?
Not sure what powder Winchester uses, of course it's different than we can buy but still a fast load for sure!

I used up the other box.

[GunnyMack]

Gotcha, would have been good to shoot some of the other box under different conditions along with the new box.

[Scott Tschirhart]

I occasionally buy a box or two because this is a predictable load that shoots very well in my Marlin carbine (which doesn’t shoot cast bullets that well).

Recoil seems the same box to box and lot to lot. I think I just had something wrong with the chronograph or the conditions’were not conducive to accurate readings.

[Scott Tschirhart]

I’m backing off to 20 gr of 2400 to see if that shoots well.

[GunnyMack]

Most likely you are correct in a fluke with your chronograph Scott.

[bmtshooter]

I have seen strange numbers from my chronograph on clear bright blue sky days. Seems to work more consistently when it is overcast for some reason.

It is electronic .......what could possibly go wrong?